title: DNA-based highly tunable particle focuser.
abstract: DNA is distinguished by both long length and structural rigidity. Classical polymer theories predict that DNA enhances the non-Newtonian elastic properties of its dilute solution more significantly than common synthetic flexible polymers because of its larger size and longer relaxation time. Here we exploit this property to report that under Poiseuille microflow, rigid spherical particles laterally migrate and form a tightly focused stream in an extremely dilute DNA solution (0.0005 (w/v)%). By the use of the DNA solution, we achieve highly efficient focusing (>99.5%) over an unprecedented wide range of flow rates (ratio of maximum to minimum flow rates ~400). This highly tunable particle-focusing technique can be used in the design of cost-effective portable flow cytometers, high-throughput cell analysis and also for cell sorting by size. We demonstrate that DNA is an efficient elasticity enhancer, which originates from its unique structural properties.
authors.affiliation: 1] Department of Chemical Engineering, Ajou University, Suwon 443-749, Republic of Korea [2] Department of Energy Systems Research, Ajou University, Suwon 443-749, Republic of Korea.
authors.forename: Kyowon
authors.initials: K
authors.lastname: Kang
authors.forename: Sung Sik
authors.initials: SS
authors.lastname: Lee
authors.forename: Kyu
authors.initials: K
authors.lastname: Hyun
authors.forename: Seong Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Ju Min
authors.initials: JM
authors.lastname: Kim
mesh_terms: D010582:Bacteriophage lambda / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D004279:DNA, Viral / Q000737:chemistry*; D004548:Elasticity; D005434:Flow Cytometry / Q000295:instrumentation / Q000379:methods*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D010316:Particle Size; D012996:Solutions; D014783:Viscosity
chemical_list: D004279:DNA, Viral; D012996:Solutions; D004247:DNA